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arXiv · 0706.4255

Quantum key distribution over 25 km with an all-fiber continuous-variable system

Jerome Lodewyck·Matthieu Bloch·Raul Garcia-Patron·Simon Fossier·Evgueni Karpov·Eleni Diamanti·Thierry Debuisschert·Nicolas J. Cerf·Rosa Tualle-Brouri·Steven W. McLaughlin·Philippe Grangier
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Abstract

We report on the implementation of a reverse-reconciliated coherent-state continuous-variable quantum key distribution system, with which we generated secret keys at a rate of more than 2 kb/s over 25 km of optical fiber. Time multiplexing is used to transmit both the signal and phase reference in the same optical fiber. Our system includes all experimental aspects required for a field implementation of a quantum key distribution setup. Real-time reverse reconciliation is achieved by using fast and efficient LDPC error correcting codes.

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Jerome Lodewyck, Matthieu Bloch, Raul Garcia-Patron, Simon Fossier, Evgueni Karpov, Eleni Diamanti, Thierry Debuisschert, Nicolas J. Cerf, Rosa Tualle-Brouri, Steven W. McLaughlin, Philippe Grangier. 2007-09-04. Quantum key distribution over 25 km with an all-fiber continuous-variable system. https://doi.org/10.1103/physreva.76.042305

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